Page 276 - Optofluidics Fundamentals, Devices, and Applications

250 Cha pte r T e n

Dye-doped ethanol

Piezoelectric
droplet generator

Pulsed input Laser emission
laser (green) from droplets (red)

(a) (b)

Water
droplet
1 mm

Silica
sphere

(c) (d)
FIGURE 10-5 Examples of optofluidic droplet dye lasers and resonators. Panels (a)
and (b) show free-falling droplets [From S. X. Qian, J. B. Snow, H. M. Tzeng, and
R. K. Chang, “Lasing droplets—highlighting the liquid-air interface by laser-emission,”
Science 231(4737), 486–488 (1986)]. Reprinted from AAAS with permission. panel
(c) shows an ultrasonically levitated droplet [H. Azzouz, L. Alkhafadiji, S. Balslev,
J. Johansson, N. A. Mortensen, S. Nilsson, and A. Kristensen, “Levitated droplet
dye laser,” Opt. Express 14(10), 4374–4379 (2006)], and panel (d) shows a droplet
trapped on an engineered substrate with silica micro spheres [M. Hossein-Zadeh
and K. J. Vahala, “Fiber-taper coupling to Whispering-Gallery modes of fluidic
resonators embedded in a liquid medium,” Opt. Express 14(22), 10,800–10,810
(2006)].